Nepenthes Edwardsiana - Cultivation

Cultivation

Nepenthes edwardsiana is very rare in cultivation and little information has been published on its growing requirements. Generally speaking, it is an alpine plant that requires highland conditions to grow well.

In 2004, professional horticulturist Robert Sacilotto wrote a summary of measured tolerances of highland Nepenthes species, based on experiments conducted between 1996 and 2001. Out of all of the studied species, N. edwardsiana proved to be the most challenging. Cotyledon-stage seedlings showed a 100% mortality rate when exposed to the following conditions: relative humidity constantly over 90%, water droplets present on the leaves, soil conductivity over 45 microsiemens, and soil pH above 6. However, several plants grew well in a substrate consisting of 50% perlite, 30% Sphagnum moss, 10% peat moss chunks, and 10% fir bark. A top dressing of live Sphagnum was found to provide a good anchoring point for developing roots. Humidity levels of 65 to 85% appeared to be optimal, although more mature plants over 1 year old were able to tolerate exposure to relative humidity in the range of 90 to 99% for up to three days. The highest growth rate was exhibited by plants that experienced warm days, with temperatures of 21 to 29 °C (70 to 84 °F), and cool nights, with temperatures of 13 to 16 °C (55 to 61 °F). The seedlings grew very slowly during the first 8 months, but their growth rate increased significantly after they reached approximately 2 cm in diameter. The plants were grown under High Pressure Sodium lamps. Optimal light intensity seemed to be in the region of 7500-9100 lx (700-850 fc). Soil with a pH of 4.8 to 5.4 and conductivity of less than 24 microsiemens produced the best results. Dried fruit fly larvae of the species Drosophila melanogaster were fed to the plants once their pitchers reached around 3 mm in height. As the pitchers increased in size, they were fed with ants (Acanthomyops sp.).